Race42012.com released its VP power rankings for March, and a surprise contender to be No. 2 on the Republican presidential ticket tops the list.

Sen. Rob Portman (R-Ohio) is “a proven vote getter in perhaps the nation’s most important swing state,” the site states.

Portman succeeded retiring GOP Sen. George Voinovich just last year. Previously, he was director of the Office of Management and Budget and the U.S. Trade Representative under President George W. Bush.

The 56-year-old Cincinnati native was also a member of the House of Representatives from 1993 to 2005.

Former Massachusetts Gov. Mitt Romney won 38 delegates in the Ohio primary; former Sen. Rick Santorum (R-Pa.) picked up 21.

Rounding out the rest of Race42012′s list:

  • Sen. Marco Rubio (R-Fla.)
  • Gov. Chris Christie (R-N.J.)
  • House Budget Committee Chairman Paul Ryan (R-Wis.)
  • Gov. Bob McDonnell (R-Va.)
  • Gov. Bobby Jindal (R-La.)
  • Rep. Cathy McMorris Rodgers (R-Wash.); highest-ranking Republican woman in the House
  • Gov. Jeb Bush (R-Fla.)
  • Sen. Pat Toomey (R-Pa.)
  • Sen. John Thune (R-S.D.)